75Mbps GH1 Peak Reliability Patch - V2 update

[meinyvr]

Very nice footage, here's a few tips:

* OIS is ok, but turn off all-exposure features. Shoot in Manual Exposure Creative Movie Mode.
* Make sure the white snow is not over-exposed, try shooting one-stop underexposed.
* Don't zoom during a take, the electronic 14-140mm zoom will bog down the camera CPU.

Thank you for the info.

The problem I'm having in Manual Exposure Creative Movie Mode (that's the mode with the little camera and M) is that I can control aperture and speed and iso BUT not exposure compensation. Do I have to abandon "M" in exposure mode to get access to exposure compensation? It looks like if I pick "S" in exposure mode I can get access to shutter speed and exposure compensation but not aperture lol.

Is this a compromise that we have to live with. If so, lpowell, which exposure mode should I mainly use then? m, s, a , p?

Thanks

 

[screwbiedooo]

This is the first hack I have properly had working on my GH1 (Nick Bartleet's old camera btw) and I can say I am really impressed with the quality coming from it. Thank you lpowell for this. It is a little juddery in the pan but generally it's a really nice image coming from the camera. Way better than before.

@meinyvr ^^^ If you are using M mode there is no need for exposure compensation. EC is a function of automatic modes (P, A, S), it has no relevance in manual since you are setting both your shutter and your aperture separately.

 

[geist_hu]

hi,

i'm new to this forums and new in film making,
i want to shoot web videos and i don't like 24/25fps, is there a way to get 30fps (AVCHD/1080p) on the Gh1?

If not, why?

2nd:
If 1080p/30fps not possible, are those 1536x864 pixels in MJPEG real pixels, or just upscaled?
Is this an option for shooting web videos, or do i have to use 720p?

Thanks!

 

[kbeezie]

So on this old thread I'm curious as to the 'proper' way of making sure I'm using all the recorded data when I'm transcoding.

Davinci Resolve (12.5.6, not the studio edition) can't handle AVCHD MTS files (basically if you try, you get no audio, and it shows a broken video when using any of the FHD sources in the interlaced format, it 'appears' to work with the progressive 720/59.97p but course no audio imported), so as a result would have to transcode it over to something like either ProRes or in my case DNxHD (which I currently do with Aiseesoft MTS converter).

My question though is, when I do the transcoding, do I want to set the target to the same as the detected rate of 29.97 (not entirely certain if the software is retaining the pulldown, or if it's interpreting frame by frame as it transcode), or do I want to set the destination as 24p output (again, with the possible assuming that it's pulling down the source).

My concern course is if I do either, it's not taking advantage of the additional data in the video and is just dropping frames in the transcoded destination.

Figure since I have to transcode anyways for my editor of choice, I wouldn't be saved really any convenience for using native 24p, and would prefer to use this patch if it benefits from cleaner/fuller data.

Edit (almost a year later followup)


Just in case someone was wondering, if I leave this patch as is, I haven't quite figured out in something like AseeSoft converter to transcode to DNxHD if it's automatically doing the pulldown or not, but no adverse effect could be seen either way once it's been pulled into the editor.

However using a custom user ini setting from humpman (his patch, the latest version January 2017 being on page 10, mainly only concentrates on FHD AVCHD mode, to address obtaining good detail in low light), I loaded up the 75mbit patch as is, and just turned on the 2997i to 2400 option,

which is basically :

[Patch8]
Name=2997i to 2400
Target=GH1 v1.32

E1_Offset=0x4014CB9A
E1_Check=0x0BB5
E1_Type=word
E1_Modify=0x0960

E2_Offset=0x4014D192
E2_Check=0x0BB5
E2_Type=word
E2_Modify=0x0960

[Patch9]
Name=2997i to 2397
Target=GH1 v1.32

E1_Offset=0x4014CB9A
E1_Check=0x0BB5
E1_Type=word
E1_Modify=0x095D

E2_Offset=0x4014D192
E2_Check=0x0BB5
E2_Type=word
E2_Modify=0x095D

The result makes the encoding 48i so that it's a straight translation to 24p (or 23.97p if using the second one) off the camera without the struggles of enabling the native 24p patch and keeping the stability of interlaced mode, and without having to deal with 3:2 pull down from 29.97i. It basically just shows up as 24p in any editor that supports AVCHD outright.

He mainly went 48i because it helped solve a diagonal rain problem in June 2016:

@yskunto seems like i solved it, i just turned it to 48i mode and rain is gone, so my theories was right it was just the 3:2 pulldown problem.

Ok then, you got me, here is the universal settings for both PAL and NTSC. Max bitrate for PAL ~68Mbps, NTSC ~63Mbps. Also i turned mjpeg mode to timelapse mode, 2 fps.
What i recognized today is that 50/60p doesn't reacting on bitrate hack, i loaded the "75Mbps Peak Reliability Patch v2" but bitrate in 50/60p mode is still doesn't go higher then 17Mbps, so i let it as it been.

The main reason I would still use the 75mbps patch here (but with the 48i mode enabled) is because all the modes remain reliable in situations where I can't just reshoot it. Whereas his patch it is mainly focused on FHD AVCHD and using any other mode may not be considered reliable (Especially 720p playback). But appears to do a very good job at maintaining detail in dark areas especially at lower ISO making sure that the data rate doesn't just fall off just because the light gets low.